This invention relates to electrical cable equipment that is to be subjected to high environmental pressures. In particular, the invention provides electrical cable equipment in which the cable components, including at least the cable jacket and cable conductors, receive only minimal mechanical stresses when in a deep underwater or other high-pressure environment.
The invention achieves this objective with a construction that essentially equalizes the pressure within the cable outer jacket and the environmental pressure.
Cable equipment constructed in accordance with the invention can be used, by way of example, in unpressurized compartments of ships or submarines, and to interconnect submerged vessels or equipment with other like equipment or with surface equipment.
Undersea electrical cables constructed in accordance with the prior art typically have outer casings constructed to withstand the large pressures encountered deep below the earth's surface. For example, cables for interconnecting compartments of a submarine frequently employ a "water-block" construction in which individually insulated conductors are bundled together within a heavy armored sheath that withstands the hydrostatic pressures. However, when these prior cables are subjected to large changes in environmental pressure, such as the pressure change between the ocean surface and the ocean floor, or when they are subjected to repeated pressure-cycling or mechanical flexing, the pressure-tight construction is likely to break up internally causing electrical failure. Also, these prior constructions for marine cables are generally relatively complex and costly, particularly if small quantities are involved. A further problem with prior art marine cables is that they often must be handled with care, such as during spooling or winching, to ensure that the internal conductors are not bent too sharply or too quickly, or otherwise damaged.
Accordingly, an object of this invention is to provide electrical cable equipment for use in deep underwater and like high-pressure environments without subjecting the components thereof to large pressure differentials or excessive mechanical stresses.
Another object of the invention is to provide cable equipment of the above character that subjects the cable jacket and the electrical conductors therein to only relatively small changes in mechanical stress and/or flexure when the environmental pressure of the cable changes considerably or repeatedly.
It is also an object of the invention to provide a cable connector for connection with an electrical cable having the interior thereof sealed from the environmental fluid, but at essentially the same pressure.
Another object of the invention is to provide cable equipment of the above character that is relatively low in cost and which withstands rough handling.
Other objects of the invention will in part be obvious and will in part appear hereinafter.